Body Fat as Determinant of Female Gonadal Dysfunction

At fasting and after an oral glucose challenge: Circulating concentrations of Leptin, Adiponectin, Chemerin, Lipocalin-2, Adipsin, Plasminogen Activator Inhibitor (PAI)-1, Monocyte Chemoattractant Protein (MCP)-1, and Soluble Leptin Receptor by multianalyte profiling on the Luminex Magpix system (Luminex Technologies, Austin, USA.).

At fasting and after an oral glucose challenge: Circulating concentrations of Amylin, C-Peptide, Ghrelin, Gastric Inhibitory Peptide (GIP), Glucagon-Like Peptide (GLP)-1, Glucagon, IL-6, Insulin, Pancreatic Polypeptide (PP), Peptide YY, Tumor Necrosis Factor (TNF)-α by multianalyte profiling on the Luminex Magpix system (Luminex Technologies, Austin, USA.).

Body mass index in in kg/m^2. Sex steroids (including circulating total testosterone, estradiol, androstenedione, dehydroepiandrosterone-sulphate and estrone) measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Free testosterone will be calculated from total testosterone and sex hormone binding globulin levels.

Fat mass% by bioelectric impedanciometry and DEXA. Sex steroids (including circulating total testosterone, estradiol, androstenedione, dehydroepiandrosterone-sulphate and estrone) measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Free testosterone will be calculated from total testosterone and sex hormone binding globulin levels.

Lean mass% by bioelectric impedanciometry and DEXA. Sex steroids (including circulating total testosterone, estradiol, androstenedione, dehydroepiandrosterone-sulphate and estrone) measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Free testosterone will be calculated from total testosterone and sex hormone binding globulin levels.

Adipose tissue depots will be estimated using a Toshiba Nemio XG SSA-580A Diagnostic Ultrasound System. Minimum sc and preperitoneal fat thicknesses will be measured at the level of the xyphoid process. Maximum sc fat thickness will be measured at the level of the umbilicus. Intraperitoneal fat thickness will be measured placing a probe transversally in the midline of abdomen, 2 cm above the umbilicus. Three measures of ip fat thickness will be obtained: the distance from the fascia of rectus abdominis muscle to the vertebral column, the distance from the peritoneum to the vertebral column, and the distance from the linea alba to the vertebral column. Perirenal fat thickness will be estimated as the distance from the perirenal fascia to the renal surface. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Fasting glucose and insulin levels will be used for calculating the homeostasis model assessment of insulin resistance (HOMA-IR), and the composite insulin sensitivity index will be estimated from the glucose and insulin concentrations measured during the oral glucose tolerance test. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Circulating HDL-cholesterol and phospholipid levels will be measured by enzymatic methods after precipitation of plasma with phosphotungstic acid and Mg2+. Total cholesterol and triglyceride levels will be determined by enzymatic methods. LDL-cholesterol concentrations will be estimated by Friedewald's equation. Circulating apolipoprotein (Apo) AI, Apo B100, and lipoprotein (a) levels will be determined by kinetic immunonephelometry. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Office blood pressure will be determined as the mean of three manual sphygmomanometer readings in the sitting position. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Twenty-four-hour ambulatory blood pressure monitoring will be performed using an A&D TM2430EX oscillometric device (A&D Co., Ltd., Tokyo, Japan). The cuff (12 × 22 cm for lean participants, 14 × 30 cm for overweight or obese participants) will placed on the nondominant arm in every woman. The period from 0700 to 2300 h will be considered daytime, and from 2300 until 0700 h the next day will be considered nighttime, reflecting the usual sleeping habits of Spaniards. Systolic, diastolic, and mean blood pressure as well as heart rate will be measured every 20 min during daytime and every 30 min during nighttime. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Cardiovascular autonomic function will be assessed by the blood pressure and heart rate responses to active standing, and Ewing and Clarke's tests. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Imaging will be conducted using a high-resolution 7.5-MHz phased-array transducer by the same trained operator in all the participants. Sex steroids will be measured as previously described.

Fat mass, lean mass and body fat depots will be measured as previously described. Oxidative stress profile will be measured by enzymatic assays: Plasma thiobarbituric acid reactive substances, total antioxidant capacity, nitrotyrosine, protein carbonyl groups and erythrocyte glutathione peroxidase levels. Sex steroids will be measured as previously described.

Participants will be instructed to collect fecal and salivary samples. DNA samples wil be used for massive sequencing of 16S ribosomal DNA (rDNA) amplicons in a MiSeq platform (Illumina). The bacterial diversity will be estimated by using Shannon, Chao 1, Jaccard, and Sorensen indexes with their SDs. Taxonomic affiliations will be assigned by using the RDP_classifier from the Ribosomal Database Project (RDP), and readings with RDP score value <0.8 will be assigned to the upper taxonomic rank, leaving the last rank as unidentified. Sex steroids will be measured as previously described.